package cn.java59;

import java.util.Scanner;

public class Demo10 {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("请输入半径:");
		double R = sc.nextDouble();
		System.out.println("半径为" + R);
		final double I = 3.14;
		double perimeter = 2 * R * I;
		double proportion = R * R * I;

		System.out.println("周长:" + perimeter);
		System.out.println("面积:" + proportion);

	}

}
